To plot velocity in VPython, one must first understand that while the documentation primarily focuses on position, velocity can be derived from position data. If you can plot position versus time, you can also plot velocity by calculating it as the derivative of position with respect to time. This can be done either by using an algebraic expression for position and differentiating it or by computing numerical derivatives from position data stored in an array. Unlike some other software that may automate this process, VPython requires users to manually compute the velocity or find a routine to assist with this calculation.